1. Field of the Invention
This invention relates to a composite armor structure which is adapted to prevent penetration of projectiles and resist rearwardly directed spalling of portions of the armor material. More specifically, the composite armor structure of this invention is adapted to provide effective resistance to shell fragment penetration, while preventing such spalling and providing significant weight saving advantages.
2. Description of the Prior Art
Various forms of composite armor structure which are suitable for effectively resisting penetration by armor piercing projectiles have been known. Many of these structures employ multiple layers of metal armor components with or without interposed non-metallic materials. See U.S. Pat. Nos. 3,157,090, 3,179,553, 3,351,374, 3,431,818 and 3,516,898. Some of these prior disclosures involve structures which provide specifically configurated deflecting elements which are interposed between interior and exterior plate-like elements. Others rely upon selection of a specific combination of materials which are adapted to function in the desired fashion.
While there have been numerous armor composite structures which effectively resist penetration of armor projectiles therethrough, there remains the problem of undesired and potentially hazardous spalling of armor materials resulting from impact by shell fragments. Also, many high strength armor structures which possess good resistance to penetration by armor piercing projectiles have inferior resistance to attack by shell fragments. There remains, therefore, a need for a composite armor structure which will effectively resist penetration by shell fragments, as determined by ballistic tests with fragment simulating projectiles (MIL-P-46593A ORD), and also prevent undesired rearward discharge of spalled materials.